Since Embedded Thin film resistors or ETFR can shorten the transmission distance, reduce electromagnetic interference, decrease the installation cost, save the space of the circuit board, it has been broadly adopted in printed wiring board (PWB)
Resistor layers can be formed conductive polymer coating, chemical plating method, Chemical vapor deposition, or Physical vapor deposition, particularly sputtering. The most common ETFR currently is Copper foil coated with Ni/Cr alloy.
Figures cited from 2011 International Symposium on Advanced Packaging Materials (APM 2011)
The application process of ETFR can be shown in the following figure from Gould Electronics Inc.
